1. Field of the Invention
The present invention relates to an electric power generation control for an alternator of a vehicle.
2. Related Art
An electric power generation control apparatus is used to control power generation of an alternator of a vehicle, which charges a vehicle-mounted battery and supplies electric power to various vehicle-mounted electric devices. The control apparatus is recently designed to optimize the power generation operation of the alternator in response to changes in operating conditions of the vehicle.
In JP-A-5-268733, power generation of the alternator is controlled by a PWM signal received from an engine control unit.
In JP-A-8-275407, power generation of the alternator is controlled in response to vehicle condition signals received from an engine control unit. The vehicle condition signals are transmitted serially through a signal line. In a serial communication, the signals transmitted are susceptible to noise and data transmission speed is limited. Therefore, integrated circuits are necessitated in both power generation control apparatus and engine control apparatus separately.
In JP-A-7-184330, not only power generation of the alternator is controlled by a control signal received from an engine control unit, but also produces a diagnosis result when an output mode signal is received through the same signal line. However, a more complicated power generation control is not enabled in the case that a plurality of control signals are received from the engine control unit.
In JP-A-6-261464, power generation of the alternator is controlled by signal transmitting and receiving operations with an engine control unit.